Telephone system



H. P CLAUSEN AND C. L. G'OODRUM.

TELEPHONE SYSTEM.

APPLICATION FILED DEC.28, 1918.

1,875,276. Patented Apr. 19, 1921 \I: x-x L18 L13 r 1 I Fg E w-\ /n ve n fa 6. Hen ry/Pfi/ausen Char/es L G aadkum HENRY P. CLAUSEN, OF MOUNT VERNON, AND CHARLES L. GOODRUM, OF NEW YORK, N. Y1, ASSIGNORS T WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW- YORK, N. Y., A CORPORATION OF NEW YORK.

" TELEPHONE SYSTEM.

' in the county of W'estchester and State of New York, and at New York, in the county of New York and State of New York, respectively, have invented certain new and useful Improvements in Telephone Systems, of which the following is a full, clear, concise and exact description.

This invention relates to improvements in telephone systems and has particular reference to systems in which inter-office or intercity trunk line circuits are used.

The common practice, insuch systems, is

to establish a connection'between two remotely separated exchanges by joining together, through any suitable connecting means at other intermediate exchanges, normally independent trunk circuits interconnecting said intermediate exchanges.

An object of this invention is to provide improved signaling means for such a system, whereby the operators at the several exchanges may readily determine the condition of the various interconnecting trunk circuits and thereby expedite the establishment of a connection. 7 1 V In accordance with this object, when all trunks connecting one exchange with any other are simultaneously busy a signal is operated to indicate such condition.

The inventive idea involved is capable of receiving a variety of expressions, one of which, for the purpose of illustrating the invention, is shown in the accompanying drawlng; but 1t is to be expressly understood that said drawing is employed merely for the purpose of facilitatingthe description of the invention as a whole and not to and are controlled by means of synchronized I distributers.

I Specification of Letters Patent. Patented App, 19, 1%21, Application fil ed December 28, 1918. 'SerialNo. 268,662.

In the drawing four exchanges A, B, C and D are shown although it will be understood that the number of these exchanges may vary in accordance with working conditions,

exchange A. is shown as consisting of jacks l, 2 and 8 but the number of these jacks may also vary. Relays 4', 5 and 6 are associated with the respective jacks 1, 2 and 3 and the arinatures and contacts of said relays are connected in series so that when all of the jacks are busy, a ground for said armatures will be found at the armature of relay 4. A

trunk 7 is employed for interconnecting jack 1 with the jack 8 at exchange B and this latter jack has likewise associatedtherewith relay 9, the armature of which has ground connected thereto. The apparatus at exchange B also comprises another jack 10 for extending the trunk 7 to another trunk 11 leading to the jack 12 at exchange 0, and said jacks 10 and 12 are provided respectively with relays 13 and 14. For extending trunks 7 and 11 to exchange D, a trunk 15 is employed for interconnecting jacks 16 and 17 at said exchanges and the respective jacks have relays 18 and 19 associated therewith. Exchange C further comprises jacks 20 and 21 having relays 22 and 23 connected thereto, the jack 20 being connected directly to jack 2 at Xchange A by means of trunk 24. nected to jack 55 at exchange D by means of trunk 25, and associated with said jack 55 is a relay 26. Similarly, exchange B further comprises acks 27 and 28, and associated relays 29 and 30 and jack 2'? is connected tojack 3 at exchange A by means of trunk 31, while jack 28 is connected to jack 32 and its associated relay '33 at exchange D by means of trunk 34.

The exchanges are provided respectively with synchronized distributers 85, '36, 37 and 38, which may be of any construction well known in the art, and which are all interconnected by a conductor 39 for controlling suitable signaling means at the various exchanges. These signaling means preferably comprise lamps 40 and 41 at exchange A, lamp 42 at exchange B, lamp 43 atexchange C and lamps 44 and 45 at exchange D-and said lamps areoperated in a manner to appear to indicate the condition of the various interconnecting trunk circuits.

Jack 21 at exchange G is con-' v 41 to ground.

to the terminals of said trunk.

It is now believed that the invention will be fully understood from a detailed descrip- 7 and 31. are busy, then-it-will only be possible for the operator at exchange A to make connection directly to jack 20 at exchange C over trunk .24. The condition of this trunk may also be determined by signaling means similar to that ust referred to and connected In a like manner, such signaling means may be employed for designating the condition of trunks which directly connect the various exchanges. If all trunks leading from exchange B toward exchanges C and D are busy, relays 13 and 30 will be energized in a manner well known in the art and a circuit will be intermittently closed for relay 46 associated with lamp 41 at exchange A, said circuit extending from grounded battery,

winding of relay 46, contact .47 of distributer 35, the wiper of said distributer, conductor 39, wiper of distributer 36, contact 48 thereof, front contacts and armatures of relays 30 and 13 to ground. Energization of relay 46 will establish a circuit for lamp 41 extending from grounded battery, front contact and armature of relay 46' and lamp Flashing of this lamp will indicate to the operator at exchange A that a connection cannot be established with exchange D over trunks extending from jacks 10 and 28. Similarly should trunks connected to jacks 12 and 20 of exchange G be tributers 35 and 36. Should relays 18 and 23 at exchange 0 be energized, a ground-will be placed upon contact 50 of distributer 37 and as the wiper thereof passes over said contact, a circuit will be closed for relay 51 at exchange A extending from grounded battcry, winding of relay 51, contact 52 of distributer 35, wiper thereof, conductor 39,

wiper 37, contact 50, front contacts and armatures of relays 23 and 18 to ground.

Relay 51 will then energize and close a circuit for lamp 40 extending from grounded battery, front contact and armature of relay 51 and lamp 40 to ground. Flashing of this lamp will indicate to the operator at ex change A that trunk circuits extending from exchange C toward exchange D are busy.

i If all trunks leading from exchange D are busy, relays 19, 26 and 33 will be energized. anda groundwill be placed upon contact 53 of distributer 38, which has aposition corresponding to contact 50 of distributer 37 and through the medium of the wiper of distributer 38 and conductor 39, it will be obvious that relay 51 will be energized in the same manner as previously described and lamp 4O operated.

In the same manner, should the operator at exchange B desire to establish connection to exchange B, lamp 42 will indicate the lamp 43 at exchange C will be lighted to indicate to the operators at such exchanges that connections cannot be established to other exchanges should all the trunks leading thereto be busy. The lamps at said exchanges C and D are operated by the energization of therelays associated therewith, when the wipers of the several distributers pass over contacts upon which ground has been placed by the contemporaneous energization of relays at the various exchanges to which busy trunks are connected.

What is claimed is: 1. In a telephone system, a plurality of exchanges, a plurality of trunk circuits for establishing connections between said exchanges, means at each exchange for indicating the condition of trunk circuits interconnecting other exchanges, and means operating in synchronism for controlling the first named means. 7 v .2. In a telephone system, a plurality of exchanges, a plurality of trunkcircuits for establishing connections between said exchanges, means at each exchange for indi-. cating the condition of trunk circuits interconnecting other exchanges, a :conductor' connecting various exchanges, and means connected to said conductor and operating in synchronism to means;

3. In a telephone system, two widely sepa-; rated exchanges, intermediateexchanges, a plurality of trunk circuits for. establishing connection between "said exchanges, means control the indicating at each exchange for indicating the condi tlon' of trunk circults interconnecting other exchanges and means operating in synchronism for controlling the first named means. 4. In a telephone. system, two widely separated exchanges, intermediate exchanges, a

plurality of trunk circuits for establishing connection between said exchanges, means at each exchange for indicating the condition of trunk circuits interconnecting other exchanges, a conductor connecting the various exchanges, and distributers connected to said conductor at said exchanges respectively, and operating in synchronism to control said indicating means.

5. In a telephone system, a plurality of exchanges, a plurality of trunk circuits, for establishing connections between said exchanges, relays associated with the terminals of said trunk circuits, the contacts of the relays for corresponding terminals of all trunk circuits interconnecting certain exchanges'being connected in series, means at each exchange for indicating the condition of trunk circuits interconnecting other exchanges, and means operating in synchronism for controlling the first named means.

6. In a telephone system, a plurality of exchanges, a plurality of trunk circuits for establishing connections between said exchanges, relays associated with the terminals of said trunk circuits, the contacts of the relays for corresponding terminals of all trunk circuits interconnecting certain exchanges being connected in series, means at each exchange for indicating the condition of trunk circuits interconnecting other exchanges, a conductor connecting the various exchanges, and means connected to said conductor and operating in synchronism to control said indicating means.

7. In atelephone system, widely separated exchanges, intermediate exchanges, a plurality of trunk circuits for establishing connection between said exchanges, relays as sociated with the terminals of trunk circuits, the contacts of the relays for corresponding terminals of all trunk circuits interconnecting certain exchanges being connected in series, means at each exchange for indicating the condition of the trunk circuits interconnecting other exchanges, and means operating in synchronism for controlling the first named means.

8. In a telephone system,widely separated exchanges, intermediate exchanges, a plurality of trunk circuits for establishing connection between said exchanges, relays associated with the terminals of trunk circuits, the contacts of the relays for corresponding terminals of all trunk circuits interconnecting certain exchanges being connected in series, means at each exchange for indicating the condition of the trunk circuits interconnecting other exchanges, a conductor connecting the various exchanges, and means connected to said conductor and operating in synchronism to control said indicating means.

9. In a telephone system, a sectionalized trunk circuit, means associated with certain sections of said circuit for indicating the status of other sections, and means operating in synchronism for controlling the first named means.

10. In ,a telephone system, a plurality of exchanges, a plurality of trunk circuits for establishing connections between said exchanges, means at each exchange for indicating the condition of trunk circuits interconnecting other exchanges, and means operating in synchronism for controlling the first named means.

11. In a telephone system, a plurality of exchanges, a plurality of trunk circuits for establishing connections between said exchanges, means at each exchange to indicate the condition of the trunk circuits interconnecting other exchanges, and a distributer at each exchange operating in synchronism with distributors at the other exchanges to control said means.

12. In a telephone system, a sectionalized trunk circuit, means associated with certain sections of said circuit for indicating the status of other sections and distributers operating in synchronism for controlling said means. i

In witness whereof, we hereunto subscribe our names this 12th day of December A. 1)., 1918.

HENRY P. CLAUSEN. CHARLES L. GOODRUM. 

